Full text article. Also available at https://doi.org/10.1371/journal.pone.0201814
A hidden determinant such as intimate partner violence victimization has been associated with under-five morbidity and mortality. However, there is lack of information regarding which exactly age group of under-five is more vulnerable to morbidity when their mothers exposed to intimate partner violence victimization. This study aimed to determine the effect of mothers’ exposure to intimate partner violence victimization on age groups specific under-five morbidity that could lead to mortality. The current study pooled and analyzed data from 2010 and 2016 Tanzania Demographic Health Survey datasets. We used a stratified multilevel modeling to assess the association between under-five morbidity and intimate partner violence victimization according to age groups. The Statistical approach using Stata 14 was used to adjust for clustering effect and weighted the estimates to correct for non-responses and disproportionate sampling employed during designing of the surveys. A total of 13,639 singleton live-births babies within three years prior to interview dates from the ever-married women were included in the analysis. We found a significant reduction of the three main symptoms of under-five morbidity namely; a cough with difficult or fast breathing from 21.7 to 15.7%, fever from 22.5 to 18.3%, and diarrhoea from 15.5 to 12.7% for the survey years from 2010 to 2016 respectively (P<0.05). Overall, about 40% of mothers reported experiencing any forms of intimate partner violence victimization. After adjusting for individual and cluster variables, we found that under-five in post-neonatal period (Adjusted odds ratios = 1.50; 95%CI, 1.21–1.86) and childhood period (Adjusted odds ratios = 1.40; 95%CI, 1.24–1.57) were significantly affected with morbidity when their mothers exposed to any form of intimate partner violence victimization. This analysis revealed that intimate partner violence victimization is still a major and public health problem in Tanzania that threatens child health during the period of post-neonatal and childhood. There is a need to introduce screening for intimate partner violence victimization in maternal and child care for effective monitoring and prevention of the problem.